From Viz:

After a escaping the unwanted attentions of some bored soldiers with the help of a handsome stranger, Sophie returns home only to be accosted by the infamous Witch of the Waste! The Witch lays a curse on her, turning Sophie into a creaky old woman. Sophie knows she has to leave town, and soon finds herself taking shelter in the moving castle of the dread wizard Howl...who is rumored to eat women's hearts!